diff --git a/playground/html/vite.config.js b/playground/html/vite.config.js
index b3944966fcccc2..4d029b1e835d26 100644
--- a/playground/html/vite.config.js
+++ b/playground/html/vite.config.js
@@ -41,6 +41,10 @@ module.exports = {
if (html.includes('/@vite/client')) {
throw new Error('pre transform applied at wrong time!')
}
+
+ const doctypeRE = //i
+ if (doctypeRE.test(html)) return
+
const head = `